Xdrive or Quattro

[Maximum]

Doing some further research seen quite a few problems with the a7 expensive running cost over the bmw expensive repair bills etc and my budget being 16k the bitdi is around 20 :/ where I can get the 335d xdrive withithn my budget And is there much power difference between f30 335d xdrive and the 535d f10. I find my merc a bit boring to drive just not exiting like i have driven my mates 640d that was fun to drive but the sheer size put me off of trying to park it and what not